diff --git a/pom.xml b/pom.xml
index 622e927..5cbeab4 100644
--- a/pom.xml
+++ b/pom.xml
@@ -41,6 +41,10 @@
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-web</artifactId>
         </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-validation</artifactId>
+        </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-data-jpa</artifactId>
diff --git a/src/main/java/eu/ztsh/wymiana/validation/Adult.java b/src/main/java/eu/ztsh/wymiana/validation/Adult.java
new file mode 100644
index 0000000..affba90
--- /dev/null
+++ b/src/main/java/eu/ztsh/wymiana/validation/Adult.java
@@ -0,0 +1,24 @@
+package eu.ztsh.wymiana.validation;
+
+import jakarta.validation.Constraint;
+import jakarta.validation.Payload;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.Retention;
+import java.lang.annotation.Target;
+
+import static java.lang.annotation.ElementType.FIELD;
+import static java.lang.annotation.ElementType.PARAMETER;
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
+@Target({ FIELD, PARAMETER })
+@Retention(RUNTIME)
+@Constraint(validatedBy = AdultValidator.class)
+@Documented
+public @interface Adult {
+    String message() default "{jakarta.validation.constraints.Adult.message}";
+
+    Class<?>[] groups() default { };
+
+    Class<? extends Payload>[] payload() default { };
+}
diff --git a/src/main/java/eu/ztsh/wymiana/validation/AdultValidator.java b/src/main/java/eu/ztsh/wymiana/validation/AdultValidator.java
new file mode 100644
index 0000000..47e2255
--- /dev/null
+++ b/src/main/java/eu/ztsh/wymiana/validation/AdultValidator.java
@@ -0,0 +1,42 @@
+package eu.ztsh.wymiana.validation;
+
+import jakarta.validation.ConstraintValidator;
+import jakarta.validation.ConstraintValidatorContext;
+
+import java.time.LocalDate;
+import java.time.format.DateTimeFormatter;
+import java.time.format.DateTimeParseException;
+import java.util.Arrays;
+import java.util.Objects;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+
+public class AdultValidator implements ConstraintValidator<Adult, String> {
+
+    private final Pattern pattern = Pattern.compile("\\d{11}");
+    private final DateTimeFormatter dtf = DateTimeFormatter.ofPattern("yyyyMMdd");
+
+    @Override
+    public boolean isValid(String value, ConstraintValidatorContext context) {
+        if (!pattern.matcher(value).matches()) {
+            return false;
+        }
+        var datePart = Arrays.stream(value.substring(0, 6).split("")).map(Integer::parseInt).toArray(Integer[]::new);
+        final String prefix;
+        if (datePart[2] > 1) {
+            datePart[2] = (datePart[2] - 2);
+            prefix = "20";
+        } else {
+            prefix = "19";
+        }
+        var dateStamp = prefix.concat(Arrays.stream(datePart).map(Objects::toString).collect(Collectors.joining()));
+        try {
+            return LocalDate.parse(dateStamp, dtf)
+                .plusYears(18)
+                .isBefore(LocalDate.now(context.getClockProvider().getClock()));
+        } catch (DateTimeParseException exception) {
+            return false;
+        }
+    }
+
+}
diff --git a/src/main/java/eu/ztsh/wymiana/web/model/UserCreateRequest.java b/src/main/java/eu/ztsh/wymiana/web/model/UserCreateRequest.java
new file mode 100644
index 0000000..32d884e
--- /dev/null
+++ b/src/main/java/eu/ztsh/wymiana/web/model/UserCreateRequest.java
@@ -0,0 +1,13 @@
+package eu.ztsh.wymiana.web.model;
+
+import eu.ztsh.wymiana.validation.Adult;
+import jakarta.validation.constraints.Min;
+import jakarta.validation.constraints.NotNull;
+
+public record UserCreateRequest(
+    @NotNull String name,
+    @NotNull String surname,
+    @Adult String pesel,
+    @Min(0) int pln) {
+
+}
diff --git a/src/test/java/eu/ztsh/wymiana/validation/AdultValidatorTest.java b/src/test/java/eu/ztsh/wymiana/validation/AdultValidatorTest.java
new file mode 100644
index 0000000..ca24718
--- /dev/null
+++ b/src/test/java/eu/ztsh/wymiana/validation/AdultValidatorTest.java
@@ -0,0 +1,58 @@
+package eu.ztsh.wymiana.validation;
+
+import jakarta.validation.ConstraintValidatorContext;
+import org.hibernate.validator.internal.engine.DefaultClockProvider;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.mockito.Mockito;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class AdultValidatorTest {
+
+    private static AdultValidator validator;
+    private static ConstraintValidatorContext validatorContext;
+
+    @BeforeAll
+    static void prepare() {
+        validator = new AdultValidator();
+        validatorContext = Mockito.mock(ConstraintValidatorContext.class);
+        Mockito.when(validatorContext.getClockProvider()).thenReturn(DefaultClockProvider.INSTANCE);
+    }
+
+    @Test
+    @DisplayName("No digits in PESEL")
+    void invalidPatternTest() {
+        assertThat(call("notAPesel")).isFalse();
+    }
+
+    @Test
+    @DisplayName("Not an adult")
+    void notAnAdultTest() {
+        assertThat(call("24242400000")).isFalse();
+    }
+
+    @Test
+    @DisplayName("Adult")
+    void adultTest() {
+        assertThat(call("88010100000")).isTrue();
+    }
+
+    @Test
+    @DisplayName("Elderly person")
+    void seniorTest() {
+        assertThat(call("00010100000")).isTrue();
+    }
+
+    @Test
+    @DisplayName("Invalid date")
+    void notAValidDateTest() {
+        assertThat(call("00919100000")).isFalse();
+    }
+
+    private boolean call(String value) {
+        return validator.isValid(value, validatorContext);
+    }
+
+}